Power line networks interconnect practically every home and business in the United States. It would be highly desirable to utilize this established infrastructure to deliver digital information. A system of passing digital information over power line networks could be exploited in a large number of ways, including: remote meter reading, load control, status checks on switches and related electrical equipment, telemetry, and the like.
Prior art attempts to implement digital communications over power line networks have met with limited success. One problem with prior art systems is that they have relatively low data rates. In many systems, this problem is attributable to the fact that digital information can only be placed at limited locations on a carrier power signal. Another problem with prior art systems is that they can only send information in one direction. For example, some systems can only push information "upstream" from a distribution location to a substation location, but cannot pass information "downstream" from a substation location to a distribution location. Thus, bi-directional communication is not possible. Another problem with prior art systems is that they require the installation of supplemental, specialized equipment on the power line network. Examples of such equipment include signal repeaters and capacitor blocking reactors.
In view of the foregoing, it would be highly desirable to provide an improved system for implementing digital communications in a power line network.